GTP cyclohydrolase III (IPR007839)

Short name:
GTP_CycHdrlase_3

Overlapping homologous superfamilies

None.

Family relationships

None.

Description

GTP cyclohydrolase (GCH) III from Methanocaldococcus jannaschi catalyses the conversion of GTP to 2-amino-5-formylamino-6-ribosylamino-4(3H)-pyrimidinone 5'-phosphate (FAPy). The reaction requires two bound magnesium ions for the catalysis and is activated by monovalent cations such as potassium and ammonium. The enzyme is a tetramer of identical subunits; each monomer is composed of an N- and a C-terminal domain that adopt nearly superimposible structures, suggesting that the protein has arisen by gene duplication [PMID: 18052207].